Improvement in rotary pumps



UNITED STATES PATENT OFFICE.

\VILLIAM B. ALLYN, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN RoTARv PUMPS.

Specification forming part of Letters Patent No. l46,74l,dated January 27, 1874; applicatiohllkd July 24, 1813.

To all whom it may concern.' y

Be it known that I, WM. B. ALLYN, of Boston, State of Massachusetts, have invented an Improvement in Rota-ry Pumps, of which the following is a specification:

This invention is an improvement on an improved rotary pump, for which Letters Patent of the- United States, No. 104,403, were granted to me June 21, 1870.

The object of my invention is to provide increased facilities for the `ingress and egress of the water, and to obtain greater bearingsurfaee for the piston on the eccentric-wheel. rlhe rst is accomplished by constructing passages A A' in both head-plates, which connect the interior of the case with chambers B I3', from which the suction and discharge pipes extend; the second, by constructing flanges M M around the central hole of the piston G, in

which the "eccentric E works to lengthen the healing, andr forming recesses F F in the ends ot the hubs D D into which the eccentric y wheel E any1 flanges M M extend, as shown the suction-pipe extends, and the other forms a connection between the case and a similar chamber, B, to which the discharge-pipe is at-V tached.

`.In order to obtain the greatest area `of the passa-ges at the points where they connect with the cylindrical'V chamber, they may be constructed in the form shown at A A', Fig. 3, which is desirable oiif'aecount of their indirect course. This peculiar shapeis necessary to insure the openingand closing ofthe passages at the proper time by the piston, which acts as a balanced slidevalve, and isV obtained by describing a segmentof a circle concentric with and within the outer edge of the piston when it is at its highest p'oint, (according to the position of the pump, as shown in the drawings,) and again concentric with and outside of the chamber of the piston when it is at the lowest point of its revolution. 'The openings when made of any other shape must be within these lines. The remaining portion can be made in any convenient form to connect with the chambers B B.

The addition of the chambers B iB besides making it convenientito attach the pipe, also afford suitable places for an air-chamber, and an opening for priming the pump when necessary. u

In the improved form of piston no openings are made in the partition outside of the bearing, excepting that .in which `the abutment J works. ,The flanges M M project equally `on both sides of the partition, more or less, ac# cording to the length of bea-ring on the eccentric E required.

The recesses F F in the hubs D D are of sufficient depth to allow the" flanges M M to in contact with the partition in the piston.

The advantages of the addition `of the flanges M M', besides obtaining a `greater bearing, are that they allow the partition of the piston G to be made only :of suicient thickness to have the required strength, whileheretofore it had to be thick enough to get the bearing required on the eccentric thereby rcducing the lateral pressure occasioned by the partition extending through from the suction to the discharge sides of the piston from onehalf to two-thirds. This is necessary forthe reason that the piston is kept in contactwith the case by a spring situated` between theeccentric and shaft, the object of which is to a1- low the piston to reccdelwhen passing over sediment. y, It also produces a more even stream, in consequence of the partition taking up less room in theinterior of the piston, the result of which fis afmore even strainon the belt or other device used to operate the pump.

This improvement is alsoapplicablc to blowers and motors made on the same principle.

I do not claim round waterfpassages in one side of the pump; neither do I claim the pis ton G when made with a thick partition with these have been used'before; but

What I claim as new, and desire to secure F in the hubs D D', constructed and opemb by Letters Patent, is- Y ing substantially as and forv therpupoae herein 1'. The passages in the head-platos approxshown and described. mating the shape shown at A Af, Fig. 3, in

combination with the chambers B B', con- WM' IB' ALLY A struoted ais and for the purpose set forth. Vtnesses:

2. The a-nges M M on the partition of the JAS. B. BELL, piston G, in combination with the recesses F ALLAH XV. VRIGI-IT. 

